I am trying to get JSON data from a rest service. I know this is pretty simple for a GET service where you only have to provide the URI and Jasper studio can pull the data but I want to do this for a post rest service that also consumes some JSON input.
Workflow will be something like:
I am new to Jasper and am using Jasper server 6 with Japser Studio 6 but I can't find any documentation to do something like this.
I would appreciate if anyone can point me in the right direction regarding this.
The closes thing I can find is this link. From there I get that I can create a constructor which will get the data from rest service but how do I serve it to the report? Also please note that the JSON object being retrieved here is a bit complex and will have at least 2 lists with any number of items.
EDIT:
Alright so my custom adapter is like this:
package CustomDataAdapter;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import net.sf.jasperreports.engine.JRDataSource;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JRField;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClientBuilder;
import org.json.JSONObject;
public class SearchAdapter implements JRDataSource {
/**
* This will hold the JSON returned by generic search service
*/
private JSONObject json = null;
/**
* Will create the object with data retrieved from service.
*/
public SearchAdapter() {
String url = "[URL is here]";
String request = "{searchType: \"TEST\", searchTxt: \"TEST\"}";
// Setting up post client and request.
HttpClient client = HttpClientBuilder.create().build();
HttpPost post = new HttpPost(url);
HttpResponse response = null;
post.setHeader("userId", "1000");
post.setHeader("Content-Type", "application/json");
// Setting up Request payload
HttpEntity entity = null;
try {
entity = new StringEntity(request);
post.setEntity(entity);
// do post
response = client.execute(post);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// Reading Server Response
try {
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode != 200) {
throw new Exception("Search Failed");
}
BufferedReader in = new BufferedReader(new InputStreamReader(
response.getEntity().getContent()));
String inputLine;
StringBuffer resp = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
resp.append(inputLine);
}
in.close();
this.json = new JSONObject(resp.toString());
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/*
* (non-Javadoc)
*
* @see
* net.sf.jasperreports.engine.JRDataSource#getFieldValue(net.sf.jasperreports
* .engine.JRField)
*/
public Object getFieldValue(JRField field) throws JRException {
// TODO Auto-generated method
// stubhttp://community-static.jaspersoft.com/sites/default/files/images/0.png
return this.json;
}
/*
* (non-Javadoc)
*
* @see net.sf.jasperreports.engine.JRDataSource#next()
*/
public boolean next() throws JRException {
return (this.json != null);
}
/**
* Return an instance of the class that implements the custom data adapter.
*/
public static JRDataSource getDataSource() {
return new SearchAdapter();
}
}
I am able to create an adapter and the Test Connection feature in Jasper Studio also returns true but I cant get it to read any of the fields in the JSON and auto-generate the report. I only get a blank document. FYI the JSON is something like:
{
"key": "value",
"key": "value",
"key": [list],
"key": [list]
}
Well, I feel stupid now but the solution was pretty easy. Turns out you cant just return a JSON object. You need to return the fields and manually add the fields in the report.
For record purposes my final code look like this:
package CustomDataAdapter;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import net.sf.jasperreports.engine.JRDataSource;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JRField;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClientBuilder;
import org.json.JSONException;
import org.json.JSONObject;
public class SearchAdapter implements JRDataSource {
/**
* This will hold the JSON returned by generic search service
*/
private JSONObject json = null;
/**
* Ensures that we infinitely calling the service.
*/
private boolean flag = false;
/**
* Will create the object with data retrieved from service.
*/
private void setJson() {
String url = "[URL is here]";
String request = "{\"searchType\": \"Test\", \"searchTxt\": \"Test\"}";
// Setting up post client and request.
HttpClient client = HttpClientBuilder.create().build();
HttpPost post = new HttpPost(url);
HttpResponse response = null;
post.setHeader("userId", "1000");
post.setHeader("Content-Type", "application/json");
// Setting up Request payload
StringEntity entity = null;
try {
entity = new StringEntity(request);
post.setEntity(entity);
// do post
response = client.execute(post);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// Reading Server Response
try {
int statusCode = response.getStatusLine().getStatusCode();
if (statusCode != 200) {
// Thrown Exception in case things go wrong
BufferedReader in = new BufferedReader(new InputStreamReader(
response.getEntity().getContent()));
String inputLine;
StringBuffer resp = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
resp.append(inputLine);
}
in.close();
String ex = "Search Failed. Status Code: " + statusCode;
ex += "\n Error: " + resp.toString();
throw new Exception(ex);
}
BufferedReader in = new BufferedReader(new InputStreamReader(
response.getEntity().getContent()));
String inputLine;
StringBuffer resp = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
resp.append(inputLine);
}
in.close();
this.json = new JSONObject(resp.toString());
} catch (NullPointerException e) {
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/*
* (non-Javadoc)
*
* @see
* net.sf.jasperreports.engine.JRDataSource#getFieldValue(net.sf.jasperreports
* .engine.JRField)
*/
@Override
public Object getFieldValue(JRField field) throws JRException {
// TODO Auto-generated method
// stubhttp://community-static.jaspersoft.com/sites/default/files/images/0.png
try {
return this.json.get(field.getName());
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
/*
* (non-Javadoc)
*
* @see net.sf.jasperreports.engine.JRDataSource#next()
*/
@Override
public boolean next() throws JRException {
if (this.json != null && !flag) {
flag = true;
return true;
} else {
return false;
}
}
/**
* Return an instance of the class that implements the custom data adapter.
*/
public static JRDataSource getDataSource() {
SearchAdapter adapter = new SearchAdapter();
adapter.setJson();
return adapter;
}
}